How to use the rear camera? (Tizen 2.4 ~)

■ Summary
Until recently, developer can use only the front camera in Tizen web platform.
But developer can select the front or rear camera from Tizen 2.4.
Tizen 2.4 supports the "facingMode".

■ Reference Site
- http://www.w3.org/TR/mediacapture-streams/#constraints